Pirajno,F. and Hoatson,D.M.(2012): A review of Australia's Large Igneous Provinces and associated mineral systems: Implications for mantle dynamics through geological time. Ore Geology Reviews, 48, 2-54.

『オーストラリアの巨大火成岩岩石区とそれに伴う鉱物システムのレビュー:地質時代を通じてのマントルダイナミクスとの関係』


Abstract
 Australia's Large Igneous Provinces (LIPs) span almost the entire Earth's geological history, ranging from Early Archean to Recent. LIPs in continental Australia are represented by continental flood basalts, fragments of oceanic plateaux, volcanic rifted margins, layered mafic-ultramafic intrusions, sill complexes, dyke swarms and silicic-dominated volcanic provinces. In the last decade or so, several geologists have started to focus on LIPs in Australia, mainly from the perspective of their mineral potential, particularly after the discovery of the Nebo-Babel Ni-Cu-PGE deposit in the West Musgrave Province, central Australia. Wingate et al. (2004a) further advanced the inventory of LIPs with the announcement of a new LIP (ca. 1070 Ma Warakurna, extending for nearly 1500 km along an E-W trend), based on U-Pb dating of baddeleyite from mafic sills and dykes. The list of LIPs increased by including other well-known igneous provinces, such as the Fortescue, Hart-Carson, Kalkarindji (formerly known as Antrim Plateau Volcanics) and various dyke swarms (e.g., Widgiemooltha, Marnda Moorn, Gairdner). The Bunbury Basalt, although only covering a small area in the Cape Naturaliste-Cape Leeuwin Peninsula, joined the list of LIPs, due to its age links with the huge Kerguelen Plateau in the Indian Ocean. As indicated by the world-class Nebo-Babel deposit (>1 Mt contained metal) and further discoveries in the West Musgrave and in the Kimberley region, the LIPs in these regions have good mineral potential. In the case of orthomagmatic mineral systems, the selection of areas or specific intrusions requires focusing on trace- and major-element geochemical trends to filter out mafic-ultramafic intrusions that may not have undergone sulphur saturation from those that have experienced sulphur saturation from processes, such as crustal contamination. In addition, consideration must be given to hydrothermal mineral systems that may have been generated as a result of thermal energy inputs, related to the emplacement into the crust of mafic-ultramafic magmas, as exemplified by recent discoveries in the West Musgrave Province. In eastern Australia, the Early Cretaceous Whitsunday volcanic province, is the largest known silicic LIP and comparable to the Chon Aike silicic LIP in South America. The mineral potential associated with the Whitsunday province is as yet not fully assessed. Similarly, the mineral potential for the Bunbury, Tasman Dolerite and Kalkarindji volcano-plutonic provinces is poorly known and yet to be fully explored. We conclude our contribution by providing a short review of crustal and mantle dynamics associated with LIP emplacement.

Keywords: Large Igneous Provinces (LIPs); Australia; Layered intrusions; Dyke swarms; Silicic LIPs; Mineral systems; Mantle plumes』

Contents
1. Introduction
2. Australia's LIPs
 2.1. Preamble
 2.2. Archaean flood volcanism: the Fortescue Group LIP, Pilbara Craton
  2.2.1. The 2.7 Ga Fortescue flood volcanism; age and stratigraphy
   2.2.1.1. The Fortescue continental flood basalts (CFB), the end result of a long-lived mantle Archaean superplume, or a series of mantle plume event?
 2.3. Proterozoic dyke swarms in Australia
  2.3.1. Widgiemooltha dykes; 2.4 Ga
   2.3.1.1. Dyke orientations
   2.3.1.2. Ages
   2.3.1.3. Lithologies
  2.3.2. Marnda Moorn dyke swarm; 1.2 Ga
  2.3.3. Gairdner Dyke Swarm; 827 Ma
 2.4. 1.8-1.7 Ga Hart-Carson LIP, Kimberley region
  2.4.1. Carson Volcanics
  2.4.2. Hart Dolerite
 2.5. 1.6 Ga Gawler Range Volcanics and Hiltaba suite
 2.6. West Bangemall sill complex; 1.4 Ga
 2.7. Warakurna LIP; 1.07 Ga
  2.7.1. Sill complexes and mafic dykes of the Warakurna LIP
   2.7.1.1. Weld Spring Member
  2.7.2. The Warakurna LIP in the Musgrave Province
   2.7.2.1. Mafic dykes
  2.7.3. Discussion
 2.8. Kalkarindji LIP; 510 Ma
 2.9. Tasmanian dolerites
 2.10. Bunbury Basalt; 130-110 Ma
 2.11. The Whitsunday silicic volcanic province; 120-105 Ma
3. Mineral systems associated with LIPs
 3.1. Introduction
 3.2. Mafic-ultramafic-related Ni-Cu-PGE
  3.2.1. Mafic related Fe-Ti-V oxides
 3.3. Magmatic-hydrothermal
 3.4. Giant hydrothermal systems linked to emplacement if LIPs
4. Mineral systems associated with Australia's LIPs
 4.1. Mineralisation in the ca 2.4 Ga Jimberlana Dyke (Eidgiemooltha dyke swarm)
 4.2. Mineralisation in the ca 1.8 Ga Hart-Carson LIP
 4.3. Mineralisation associated with the Gawler Range Volcanics and Hiltaba Suite
  4.3.1. Olympic Dam
 4.4. Mineralisation in the Musgrave Province
  4.4.1. Mineralisation in Giles mafic-ultramafic rocks
   4.4.1.1. Wingellina nickeliferous ochres and chrysoprase
   4.4.1.2. Nebo-Babel No-Cu-(PGE) deposit
   4.4.1.3. Vanadiferous titano-magnetite
   4.4.1.4. Prospectivity analysis and discussion
 4.5. Mineral potential of Tasman Dolerite
 4.6. Giant hydrothermal circulation possibly linked to LIPs in Australia
  4.6.1. Mineral systems associated with the Whitsunday SLIP
5. LIPs and mantle dynamics in the Australian context: discussion and conclusions
 5.1. Overview
 5.2. Crustal doming, rifting, triple junctions, basin-forming events and LIPs
 5.3. Australian LIPs
Acknowledgements
Appendix A. Supplementary data
References


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